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81.
Phenolic extractives in the trunk of Toxicodendron vernicifluum (syn. Rhus verniciflua) were investigated. Seventeen compounds, gallic acid, protocatechuic acid, (?)-fisetinidol-4β-ol, (?)-fisetinidol-4α-ol, 2-benzyl-2,6,3′,4′-tetrahydroxycoumaran-3-one, (?)-fustin, 1,2,3,6-Tetra-O-galloyl-β-d-glucose, (?)-epifustin, (+)-taxifolin, 1,2,3,4,6-penta-O-galloyl-β-d-glucose, (?)-garbanzol, (?)-fustin-3-O-gallate, (?)-epifustin-3-O-gallate, fisetin, sulfuretin, quercetin and butein, were identified from the heartwood extractives. It was found that only (+)-taxifolin which had 5,7-dihydroxy A-ring possessed a 3R configuration although other flavonoids which had 7-hydroxy A-ring possessed a 3S configuration. Quantitative analysis revealed that the total phenolic contents were much higher in the heartwood (5–7 wt%) than in the sapwood and bark (1–2 wt%), and (?)-fustin was the most abundant extractive in the heartwood (1.4–2.4 wt%). For the radial distribution of phenolic extractives, it was generally found that their content was lowest in the sapwood, increased to the highest in the outer heartwood, and then decreased in the inner heartwood.  相似文献   
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Pelleted poultry manure is recommended for use with agricultural soil as a replacement for chemical fertilizers; however, application of the manure stimulates nitrous oxide (N2O) emission from the soil through denitrification. To mitigate the N2O emission caused by application of pelleted poultry manure, soil microcosms were set up; each microcosm was inoculated with one of the following N2-generating denitrifier strains previously been isolated from paddy soil: Azoarcus, Dyella, Dechloromonas, Niastella, and Burkholderia. When pelleted poultry manure was incubated on its own, N2O was produced by denitrification. In contrast, N2O emission was significantly lowered when the manure was inoculated with most of the N2-generating strains. In soil microcosms, N2O was emitted during incubation after application of the pelleted manure, while N2O flux was significantly lowered when the soil was inoculated with Azoarcus sp. KS11B, Niastella sp. KS31B, or Burkholderia sp. TSO47-3 on the 12th day of incubation. In addition, when pelleted manure was inoculated with the strains prior to application in the soil microcosms, the level of N2O emission was significantly lowered to ca. 40–60 % that from the non-inoculated control. Our study provides the prototype of a technique that uses microbial technology to mitigate N2O emission from agricultural soil fertilized with pelleted poultry manure.  相似文献   
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The objective of this study was to evaluate effects of sodium-butyrate supplementation on gastrointestinal function and the inflammatory response to ruminal acidosis (RA) challenge in cows. Four nonlactating cows with a rumen cannula were assigned to two treatments in a crossover design. Treatments were ruminal administration of sodium-butyrate (BUT) or control (CON). Sodium-butyrate was provided as Gustor BP70 and administered at a butyrate dose of 0.04% per kg body weight. The CON premix was made by replacing sodium-butyrate with wheat bran. Experimental periods were 28 days long with 21-day washout period separating the treatments. On Day 25 of each period, corn starch was ruminally administered at 0.7% per kg body weight as RA challenge. After RA challenge, ruminal pH was lower, and endotoxin concentration was higher for cows provided with BUT than those with CON, but the increase in fecal starch and the decrease in fecal pH were attenuated by BUT. The effect of butyrate supplementation on serum lipopolysaccharide-binding protein after RA challenge was not found. From these findings, butyrate supplementation mitigated rectal acidosis by reducing the flux of fermentable carbohydrate into the large intestine. An anti-inflammatory effect of butyrate was not observed, possibly due to lower pH and higher endotoxin concentration in the rumen.  相似文献   
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